Furnace discharging apparatus



Feb. 21, 1967 c. 1.. KERR FURNACE DI SCHARGING APPARATUS Filed Sept. 19,1962 3 Sheets-Sheet l H mm INVENTOR.

CECIL L. KERR his ATTORNEY Feb. 21, 1967 Filed Sept. 19, 1962 FURNACE C.L. KERR DI SCHARGING APPARATUS 3 Sheets-Sheet I:

INVENTOR. CECIL L. KERR I BY his ATTORNEY Feb. 21, 1967 c, KERR3,305,109

FURNACE DISCHARGING APPARATUS Filed Sept. 19, 1962 3 Sheets-Sheet dINVENTOR. CECIL L. KERR his ATTORNEY slides downwardly on the skids.

United States Patent Ofiice 3,305,109 FURNACE DISCHARGING APPARATUSCecil L. Kerr, Bethel Park, Pa., assignor to Amsler Morton Company, adivision of Textron Inc., Pittsburgh, Pa., a corporation of Rhode IslandFiled Sept. 19, 1962, Ser. No. 224,749 1 Claim. ((31. 214-26) Thisinvention relates to furnace apparatus and more particularly toequipment for handling slabs or other heated materials in conjunctionwith a furnace or the like.

Prior to rolling operation, it is the usual practice to pass the slabsthrough a heating furnace where they are heated to a temperaturesuitable for rolling operation. At the time the slabs are ready fordischarge from the furnace they are pushed onto inclined drop-out skidswhere they slide under force of gravity through a discharge opening ofthe furnace. A fixed abutment is located at the base of the skids inposition to stop the slabs at whatever location is desired forsubsequent conveyancing. Since the slabs have considerable velocity atthe time they impact with the stop there is a high incidence of damagewhich occurs to the slabs at the bottom of the inclined skids. While theslab i in a heated condition it is quite susceptible to such damage andcertain compositions of metal in heated condition in particular arelikely to be damaged when they impact against the stop at the bottom ofthe inclined skids.

Another shortcoming of the inclined drop-out skid method for removingslabs, is that the heating furnace should be enclosed as completely aspossible to prevent heat losses and for that purpose there are providedswinging doors which are opened on impact with a slab as it The doorshould have substantial strength to provide adequate insulation but whenconstructed in this manner, said doors also develop substantialresistance to the slabs which are thereby damaged in much the same wayas occurs when the slabs impact against stops at the end of the skids.Therefore, this described method of removing heated slabs has provedgenerally unsatisfactory.

One of the foremost objects of the present invention is to provide a newand improved method of handling heated slabs wherein the heated slabsare removed from a heating chamber without producing damage to theslabs.

A further object of the invention is to provide a slabhandling apparatusin conjunction with a heating furnace in which impact forces of variouskinds are eliminated together with the consequent damage which isproduced on the slab.

A further object of the present invention is to provide a slab-handlingmeans which effectively reduces heat losses by substantially filling theoutlet through which the slabs are withdrawn after being heated. Theonly time during which the outlet or discharge is open, is during thebrief period in which the heated slabs are transported from the interiorof the furnace to a subsequent transporting v means.

the center of a heating apparatus for slabs which heats them to asuitable temperature before rolling, said ap- 3365,19 Patented Feb. 21,1967 paratus having slab-handling equipment in accordance with thepresent invention installed thereon;

FIG. 2 is a enlarged detail view of the slab-handling apparatus shown inFIG. 1;

FIG. 3 is a detail view of the handling apparatus looking in thedirection of the arrows 3-3 in FIG. 1;

FIG. 4 is a schematic view of the actuator system for operating theslab-holding apparatus illustrated in FIGS. 1-3;

FIG. 5 illustrates a further embodiment of the slabholding apparatusindicated in FIG. 2 wherein the support surfaces are movable to providefor slab movement through a narrower exit opening of a heatingapparatus;

FIG. 6 is a further embodiment of a slab-handling apparatus in which theexit opening of the heater can be located at a lower vertical level thanthe line of movement of the slabs within the heating apparatus; and,

FIG. 7 is a yet further embodiment of the'invention in which theslab-handling apparatus moves the slab stepwise for removal from theheating apparatus.

Referring now to the drawings, the heating apparatus indicated generallyby reference numeral 10 includes a furnace chamber 12 having an inlet 14through which are passed a plurality of slabs 15 which extend crosswisein the chamber 12 and are stacked one beside the other in one continuousseries extending through the chamber 12. The slabs are caused to slideon water-cooled rails 16 which are supported on vertical members 18 andthe product of combustion from the top and bottom fired burners 20, 22at the input end and the top and bottom fired burners 24, 26 at theoutput end, are passed through vertical fiues 28 and 30.

After the slab pass through the furnace chamber 12 and are brought totemperature they then enter a soak chamber 32 which is heated by a topfired burner 34 which maintains a preferred temperature of the soakchamber 32 so that heat will uniformly permeate the crosssection of theslab before it is discharged, bringing all portions of the slab to asuitable temperature. At the end of the soak chamber 32 is an exitopening 36 in which there is received a number of slab-handling devicesdesignated generally by reference numeral 38 and spaced at intervalsalong the width of the exit opening 36 to provide generally horizontallydisposed support surfaces 40 which are located in alignment with theadvancing slabs 15 within the heating apparatus 19 to receive tereon aslab which is transferred directly from the rails 16. The surfaces 40are located at spaced intervals along the length of the slab to carrythe entire weight of the slab which is held balanced. Each of theslab-handling devices 38 is movable along an inclined ramp 42 on rollerbearings 44 and on additional bearings 46 (FIG. 2). Movement of theapparatus 38 is constrained to its reciprocable inclined plane movementby journal bearings 48 and 50 which are located on oppositesides of thestem portion 52 of the device 38. Once a slab 15 is received on thespaced slabhandling devices 38 it is transferred without occurrence ofshock load to the slab, down the including ramp 42 and is deposited on acourse of rollers 52 which are journaled at opposite ends on I-beam 54and journal box 56, respectively. The slab is deposited on the rollerbearings by movement of the support surfaces 40 to the dotted lineposition shown in FIG. 2 which is just below the surface of the courseof roller bearings 52. The slab 15 is then caused to move longitudinallyto a subsequent operation such as rolling or the like.

The slab 15 is moved from the chamber 32 onto the bearings 52 withoutoccurrence of any shock loads which occur from impacts such aspreviously experienced where the slabs were caused to slide downinclined skids and them impacted against a stop at the base of theskids. Instead, the device 38 translates the slab 15 without anyrelative movement occurring between the device 38 and slab until theslab is deposited by gradually lowering the surface 48 below the surfaceof the bearings 52. The device 38 is operated by 'ahydrau'lic orpneumatic motor 58 (FIG. 3) comprising a double acting piston 60received within a cylinder 62 and having a piston rod 64 operativelyconnected with the device 38 to effect movement in each of oppositedirections to produce lowering and raising of the support surface 48either to lower a slab onto the bearings 52 or raise the surfaces 48 inposition to receive a successive slab 15.

The motor 58 is operated by means of a spool valve 66 which is biased byopposed springs 68 and 70 to a central position wherein the lands 71, 72interrupt communication of a pressure source 73 through line 74 witheither of the lines 76, '78 connecting to opposite sides of the piston60. In the center position of the spool valve 66 line 78 communicateschamber 58 of the motor to exhaust and chamber 62 is severed fromcommunication with either the pressure source or with exhaust therebyfixing the position of the motor at the raised position of the device 38which has a servo feed back contact 79 biasing the spool to a centerposition when the surface 46 reaches a height in position to receive asuccessive slab. The device 38 is therefore locked at such height bymovement of the spool to its centered position wherein the fluid isprevented from leaving the motor chamber 62.

When a slab 15 is deposited on surface 40 it closes a limit switch 90producing a circuit from the positive terminal of a power source such asa battery 92 through conductor 94 to a time delay relay 96 and conductor98 through closed switch 90 and conductor 1% to the negative terminal bypower source 92. The time delay relay remains engaged for a period oftime effective to translate the slab downwardly and deposit it on thecourse of rollers 52.

The time delay relay 96 closes the switch 182, opens switch 184 andcloses switch 106 through a connection 108 which is effective only forclosing but not for opening the switch 166. While the time delay relay96 is energized, a circuit is made from the positive terminal of energysource 188, conductor 110, closed switch 112, conductor 114 to coil 116of solenoid 118, conductor 120 to the other terminal of power source 108to effect rightward movement of the spool valve 66 and biasing of thepiston 68 leftwardly to lower the slab.

When the slab carrier surface reachs its lowermost position and the slab15 is deposited on rollers 52 the switch 90 opens and the time delayrelay 90 reverses opening switch 102 and switch 104 closes making acircuit from one terminal of the energy source 108 through conductor122, switch 104, conductor 124, close switch 106, conductor 126,solenoid coil 128 and conductor 100 to the negative terminal of 108.

The energized coil 128 displaces the spool 66 leftwardly communicatingthe pressure source 73 with chamber 62 to displace the piston 60 to theright and raise the device 38-. If the slab deposited on 52 is not movedout of the way of the upcoming surfaces 40 it closes switch 98 andactuates the relay 96 in a movement closing switch 102 and openingswitch 104 to energize the solenoid coil 116 such that spool 66 causes alowering of the device 38 for a further period during which the slab on52 is displaced. Then the device 38 is prevented from raising a slab 15once it is deposited on 52.

If the switch 90 is not closed during return or raising stroke of thedevice 38, the coil 116 will remain energized until switch 106 is openedby the one way switch arm 12% which is engaged by and is operated toopen position by upward movement only of the device 38 of the preparedvertical level of the support surface 48. The switches 182 and 186 nowbeing both opened deenergize both coils of the solenoid and the spool 66is in neutral position. The weight of the unit is supported by fluidtrapped in chamber 62 and blocked by the load 70 of spool 66, theportion being used by engaging a follow up i or servo abutment byengagement with a complementary portion (not shown) of the device 38which positions the spool so that fiuid in 62 cannot pass out of passage76 and therefore supports the vertical load of the device 38.

The action of the motor is quite moderate so that the slab is notsubjected to sudden starts and steps which could shake the slab off itssupport or produce any sharp imports thereon.

I have found it also useful to enlay in conjunction with the device 38 aswitch 117 which precludes charging an additional slab into the furnaceuntil the device 38 is in raised position to receive an outcoming slab.In this way there is no possibility of discharging a slab without thedevice 38 being in position to receive such a slab.

Referring next to the embodiment shown in FIG. 5, the surface 40 can besupported on a pivot 162 so that when a slab 15 is received it willoverbalance the surface '48 on pivot 162 turning it counterclockwise sothat bearings 164 will engage the inclined surface 42. In this position,the slab 15 is still retained by virtue of the finger 166 and as thedevice 38 is lowered by a mechanism of the same description as stated inthe previous embodiment (FIG. 3). The principal advantage of thearrangement as shown in FIG. 4 is that by making the support 48' pivotalit is possible to reduce accordingly the size of the exit passage 36 andthereby reduce heat loss.

In all other respects, the embodiment works the same as described in theprior embodiment.

Referring next to the embodiment disclosed in FIG. 6, there is providedan articulated linkage 38' having a trunnion 170 upon which the linkageturns to first lower the support surface 40" causing the slab 15 to movevertically downwardly within drop-out chamber 172 and then moveslaterally through a doorway 174 having a normally closed door 176 forretaining heat within the chamber. The slab 15 moves successively fromposition 15' to 15" and onto the rollers 52 where they are thendisplaced to the next succeeding operation, as for example, rolling orthe like. T his arrangement discloses the possibility of locating theexit in vertically offset relation and providing composite arcuate andlaternal withdrawal movement to the slab as distinguished from theinclined travel of the device 38 in the previous embodiments. In allother respects, the mechanism is the same.

Referring next to the embodiment shown in FIG. 7, the slab withdrawingapparatus is provided in the form of a support surface 41 which firstmoves vertically downwardly to the position shown in 40, 40' having aslab 15 thereon and then moves leftwardly to bring the slab 15 over thebearings 52 where the surface 40 then moves vertically downwardly afurther increment and deposits the slab 15 on the bearings 52. Thiscomposite movement in the form of successive vertically downward,lateral, and then additional downward movement can be provided eitherhydraulically or pneumatically, however preferred. The arrangementillustrates the disposal of exit opening 36 both downwardly andlaterally offset from the line of travel of the slabs 15 as they moveinto position for withdrawal from the chamber 32.

Although the present invention has been illustrated and described inconnection with a few selected example embodiments of the invention, itwill be understood that these are illustrative and are by no meansrestrictive of the invention. It is reasonably to be expected that thoseskilled in this art can make numerous revisions and adaptations of theinvention to suit individual design requirements. It is intended thatrevisions and adaptations by those skilled in the art which incorporatethe herein disclosed principles will be included within the scope of thefollowing claim as equivalents of the invention.

What is claimed is:

A slab-handling apparatus in combination with a slabheating apparatushaving a discharge opening at the end thereof, comprising:

(a) support means having support surfaces disposed 6 at a vertical levelfilling the major portion of said ment and subsequent return movement ofsaid supdischarge opening and disposed to receive in turn port means toa vertical location Within the disthe horizontally movable slabs movingthrough said apparatus to become transferred onto the support surfacesof said support means as an extension of the 5 charge opening and inposition to receive a subsequent slab.

support surfaces provided by the heating apparatus; References Cited bythe Examiner (b) means forming an inclined bearing for said sup- UNITEDSTATES PATENTS port means and providing a guideway for rectilinearlyreciprocable movement thereon whereby heated slabs 2 024 949 12 1935 S hf 1443 are transferred both laterally and vertically out of 10 2,061,35811/1936 Hunter a va1 214 18 the heating apparatus through sa1d dischargeopen- 2,761,507 9 /1956 Clarke et ing without aflecting the angularityof said support 3,243,059 3/1966 Kalberkamp 214-26 surfaces;

(c) a course of antifriction rollers for receiving said GERALD FORLENZA,Primary Examine!- slabs Which are deposited thereon and Without in- 1HUGO O. SCHULZ Examineh ertial displacement from said support means;

(d) and means for effecting said reciprocable move- R A AssistantExaminer.

